I don’t know if someone would agree to me but here in my location, my best option for cleaning PCB’s is only Denatured alcohol. It seems like it works for me. I have a lot of broken boards that has been repaired using this alcohol. I even use it to remove rust from my DDR3 RAM’s pins. It’s kinda old so it has rusts. I know it’s cheap but here in my location, everything is expensive so I can’t afford 99% isopropyl alcohol. Denatured alcohol is only about 25-40 ph pesos per bottle in local hardware. (roughly 0.50 USD) and everything that I repaired using Denatured alcohol is still working. I also research a lot about this alcohol but it seems like there’s no one have answers like can it be used in electronics, repairs, etc. I can’t even find an alcohol percentage of denatured bottle so I just tried it out and it works fine untill now. Hope it helps and somebody gets an attention with this. Maybe we could actually replace or have an alternatives for isopropyl alcohol.